The last time Marc Savard held a news conference at TD Garden, it was on Feb. 7, 2011, to announce that his season was over because of post-concussion syndrome. He hasn't played since Jan. 22, 2011, when he suffered his second concussion in a 10-month period. Savard returned to the Garden on Saturday to announce that he has purchased a luxury suite in the arena through the 2013-14 season that will host pediatric patients from Children's Hospital Boston, with a focus on children suffering from the effects of head trauma.